mtd: nand: lpc32xx_slc: fix calculation of timing arcs from given values

According to LPC32xx User's Manual all values measured in clock cycles
are programmable from 1 to 16 clocks (4 bits) starting from 0 in
bitfield, the current version of calculated clock cycles is too
conservative.

Correctness of 0 bitfield value (i.e. programmed 1 clock
timing) is proven with actual NAND chip devices.

Signed-off-by: Vladimir Zapolskiy <vz@mleia.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
This commit is contained in:
Vladimir Zapolskiy 2015-10-01 02:23:37 +03:00 committed by Brian Norris
parent 08d3cd5ef0
commit d54e88011d

View file

@ -95,7 +95,7 @@
* slc_tac register definitions
**********************************************************************/
/* Computation of clock cycles on basis of controller and device clock rates */
#define SLCTAC_CLOCKS(c, n, s) (min_t(u32, 1 + (c / n), 0xF) << s)
#define SLCTAC_CLOCKS(c, n, s) (min_t(u32, DIV_ROUND_UP(c, n) - 1, 0xF) << s)
/* Clock setting for RDY write sample wait time in 2*n clocks */
#define SLCTAC_WDR(n) (((n) & 0xF) << 28)